A medical porous metal material for weight-bearing bone tissue replacement and a preparation method therefor, prepared as follows: mixing tantalum powder, a pore-forming agent, and a forming agent, press-forming the powder mixture into an organic foamed body, then degreasing, sintering, cooling, and performing a heating process. The pressure used during the press-forming is 50 to 100 Mpa. The degreasing process comprises: gradually increasing the temperature to 400 to 800°C at a speed of 0.3 to 2°C/min, introducing argon gas to form a protective atmosphere, and maintaining the temperature for 300 to 360 minutes. The pore-forming agent is ammonium bicarbonate or hydrogen peroxide. The forming agent is one or multiple of stearic acid, zinc sterate, paraffin, and synthetic resin. The medical porous tantalum material produced has a diameter of 100 to 500 μm, a porosity of 55% to 65%, an elastic modulus of 3.8 to 4.2 Gpa, and an elongation rate of 9.3% to 10.7%. The final porous tantalum material prepared using the preparation method of the present invention has a low impurity concentration, thereby effectively solving the conflict that the medical porous tantalum material for weight-bearing part replacement must have both high porosity and good mechanic properties.Matériau métallique poreux de substitution dun tissu osseux de support à usage médical et son procédé de préparation, selon lequel la poudre de tantale est mélangée avec lagent de formation de pores et lagent moulant, la poudre ainsi mélangée est comprimée jusquà obtenir, dans un corps mousseux organique, le moulage, décrassage, frittage, refroidissement et traitement thermique, la pression étant comprise entre 50 et 100 MPa, le décrassage seffectuant à une température augmentant graduellement de 400 à 800° C, de telle sorte que largon forme une atmosphère protectrice et conserve la température comprise entre 300 et 360° C, lagent de formation de pores étant un bicarbonate dammonium ou un peroxyde dhydrogène,
